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llvm-mirror/lib/IR/PassManager.cpp

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2014-03-19 19:41:38 +01:00
//===- PassManager.cpp - Infrastructure for managing & running IR passes --===//
Introduce an AnalysisManager which is like a pass manager but with a lot more smarts in it. This is where most of the interesting logic that used to live in the implicit-scheduling-hackery of the old pass manager will live. Like the previous commits, note that this is a very early prototype! I expect substantial changes before this is ready to use. The core of the design is the following: - We have an AnalysisManager which can be used across a series of passes over a module. - The code setting up a pass pipeline registers the analyses available with the manager. - Individual transform passes can check than an analysis manager provides the analyses they require in order to fail-fast. - There is *no* implicit registration or scheduling. - Analysis passes are different from other passes: they produce an analysis result that is cached and made available via the analysis manager. - Cached results are invalidated automatically by the pass managers. - When a transform pass requests an analysis result, either the analysis is run to produce the result or a cached result is provided. There are a few aspects of this design that I *know* will change in subsequent commits: - Currently there is no "preservation" system, that needs to be added. - All of the analysis management should move up to the analysis library. - The analysis management needs to support at least SCC passes. Maybe loop passes. Living in the analysis library will facilitate this. - Need support for analyses which are *both* module and function passes. - Need support for pro-actively running module analyses to have cached results within a function pass manager. - Need a clear design for "immutable" passes. - Need support for requesting cached results when available and not re-running the pass even if that would be necessary. - Need more thorough testing of all of this infrastructure. There are other aspects that I view as open questions I'm hoping to resolve as I iterate a bit on the infrastructure, and especially as I start writing actual passes against this. - Should we have separate management layers for function, module, and SCC analyses? I think "yes", but I'm not yet ready to switch the code. Adding SCC support will likely resolve this definitively. - How should the 'require' functionality work? Should *that* be the only way to request results to ensure that passes always require things? - How should preservation work? - Probably some other things I'm forgetting. =] Look forward to more patches in shorter order now that this is in place. llvm-svn: 194538
2013-11-13 02:12:08 +01:00
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/PassManager.h"
Introduce an AnalysisManager which is like a pass manager but with a lot more smarts in it. This is where most of the interesting logic that used to live in the implicit-scheduling-hackery of the old pass manager will live. Like the previous commits, note that this is a very early prototype! I expect substantial changes before this is ready to use. The core of the design is the following: - We have an AnalysisManager which can be used across a series of passes over a module. - The code setting up a pass pipeline registers the analyses available with the manager. - Individual transform passes can check than an analysis manager provides the analyses they require in order to fail-fast. - There is *no* implicit registration or scheduling. - Analysis passes are different from other passes: they produce an analysis result that is cached and made available via the analysis manager. - Cached results are invalidated automatically by the pass managers. - When a transform pass requests an analysis result, either the analysis is run to produce the result or a cached result is provided. There are a few aspects of this design that I *know* will change in subsequent commits: - Currently there is no "preservation" system, that needs to be added. - All of the analysis management should move up to the analysis library. - The analysis management needs to support at least SCC passes. Maybe loop passes. Living in the analysis library will facilitate this. - Need support for analyses which are *both* module and function passes. - Need support for pro-actively running module analyses to have cached results within a function pass manager. - Need a clear design for "immutable" passes. - Need support for requesting cached results when available and not re-running the pass even if that would be necessary. - Need more thorough testing of all of this infrastructure. There are other aspects that I view as open questions I'm hoping to resolve as I iterate a bit on the infrastructure, and especially as I start writing actual passes against this. - Should we have separate management layers for function, module, and SCC analyses? I think "yes", but I'm not yet ready to switch the code. Adding SCC support will likely resolve this definitively. - How should the 'require' functionality work? Should *that* be the only way to request results to ensure that passes always require things? - How should preservation work? - Probably some other things I'm forgetting. =] Look forward to more patches in shorter order now that this is in place. llvm-svn: 194538
2013-11-13 02:12:08 +01:00
#include "llvm/ADT/STLExtras.h"
#include "llvm/IR/LLVMContext.h"
Introduce an AnalysisManager which is like a pass manager but with a lot more smarts in it. This is where most of the interesting logic that used to live in the implicit-scheduling-hackery of the old pass manager will live. Like the previous commits, note that this is a very early prototype! I expect substantial changes before this is ready to use. The core of the design is the following: - We have an AnalysisManager which can be used across a series of passes over a module. - The code setting up a pass pipeline registers the analyses available with the manager. - Individual transform passes can check than an analysis manager provides the analyses they require in order to fail-fast. - There is *no* implicit registration or scheduling. - Analysis passes are different from other passes: they produce an analysis result that is cached and made available via the analysis manager. - Cached results are invalidated automatically by the pass managers. - When a transform pass requests an analysis result, either the analysis is run to produce the result or a cached result is provided. There are a few aspects of this design that I *know* will change in subsequent commits: - Currently there is no "preservation" system, that needs to be added. - All of the analysis management should move up to the analysis library. - The analysis management needs to support at least SCC passes. Maybe loop passes. Living in the analysis library will facilitate this. - Need support for analyses which are *both* module and function passes. - Need support for pro-actively running module analyses to have cached results within a function pass manager. - Need a clear design for "immutable" passes. - Need support for requesting cached results when available and not re-running the pass even if that would be necessary. - Need more thorough testing of all of this infrastructure. There are other aspects that I view as open questions I'm hoping to resolve as I iterate a bit on the infrastructure, and especially as I start writing actual passes against this. - Should we have separate management layers for function, module, and SCC analyses? I think "yes", but I'm not yet ready to switch the code. Adding SCC support will likely resolve this definitively. - How should the 'require' functionality work? Should *that* be the only way to request results to ensure that passes always require things? - How should preservation work? - Probably some other things I'm forgetting. =] Look forward to more patches in shorter order now that this is in place. llvm-svn: 194538
2013-11-13 02:12:08 +01:00
using namespace llvm;
[PM] Support invalidation of inner analysis managers from a pass over the outer IR unit. Summary: This never really got implemented, and was very hard to test before a lot of the refactoring changes to make things more robust. But now we can test it thoroughly and cleanly, especially at the CGSCC level. The core idea is that when an inner analysis manager proxy receives the invalidation event for the outer IR unit, it needs to walk the inner IR units and propagate it to the inner analysis manager for each of those units. For example, each function in the SCC needs to get an invalidation event when the SCC gets one. The function / module interaction is somewhat boring here. This really becomes interesting in the face of analysis-backed IR units. This patch effectively handles all of the CGSCC layer's needs -- both invalidating SCC analysis and invalidating function analysis when an SCC gets invalidated. However, this second aspect doesn't really handle the LoopAnalysisManager well at this point. That one will need some change of design in order to fully integrate, because unlike the call graph, the entire function behind a LoopAnalysis's results can vanish out from under us, and we won't even have a cached API to access. I'd like to try to separate solving the loop problems into a subsequent patch though in order to keep this more focused so I've adapted them to the API and updated the tests that immediately fail, but I've not added the level of testing and validation at that layer that I have at the CGSCC layer. An important aspect of this change is that the proxy for the FunctionAnalysisManager at the SCC pass layer doesn't work like the other proxies for an inner IR unit as it doesn't directly manage the FunctionAnalysisManager and invalidation or clearing of it. This would create an ever worsening problem of dual ownership of this responsibility, split between the module-level FAM proxy and this SCC-level FAM proxy. Instead, this patch changes the SCC-level FAM proxy to work in terms of the module-level proxy and defer to it to handle much of the updates. It only does SCC-specific invalidation. This will become more important in subsequent patches that support more complex invalidaiton scenarios. Reviewers: jlebar Subscribers: mehdi_amini, mcrosier, mzolotukhin, llvm-commits Differential Revision: https://reviews.llvm.org/D27197 llvm-svn: 289317
2016-12-10 07:34:44 +01:00
// Explicit template instantiations and specialization defininitions for core
// template typedefs.
namespace llvm {
template class AllAnalysesOn<Module>;
template class AllAnalysesOn<Function>;
template class PassManager<Module>;
template class PassManager<Function>;
template class AnalysisManager<Module>;
template class AnalysisManager<Function>;
template class InnerAnalysisManagerProxy<FunctionAnalysisManager, Module>;
template class OuterAnalysisManagerProxy<ModuleAnalysisManager, Function>;
[PM] Support invalidation of inner analysis managers from a pass over the outer IR unit. Summary: This never really got implemented, and was very hard to test before a lot of the refactoring changes to make things more robust. But now we can test it thoroughly and cleanly, especially at the CGSCC level. The core idea is that when an inner analysis manager proxy receives the invalidation event for the outer IR unit, it needs to walk the inner IR units and propagate it to the inner analysis manager for each of those units. For example, each function in the SCC needs to get an invalidation event when the SCC gets one. The function / module interaction is somewhat boring here. This really becomes interesting in the face of analysis-backed IR units. This patch effectively handles all of the CGSCC layer's needs -- both invalidating SCC analysis and invalidating function analysis when an SCC gets invalidated. However, this second aspect doesn't really handle the LoopAnalysisManager well at this point. That one will need some change of design in order to fully integrate, because unlike the call graph, the entire function behind a LoopAnalysis's results can vanish out from under us, and we won't even have a cached API to access. I'd like to try to separate solving the loop problems into a subsequent patch though in order to keep this more focused so I've adapted them to the API and updated the tests that immediately fail, but I've not added the level of testing and validation at that layer that I have at the CGSCC layer. An important aspect of this change is that the proxy for the FunctionAnalysisManager at the SCC pass layer doesn't work like the other proxies for an inner IR unit as it doesn't directly manage the FunctionAnalysisManager and invalidation or clearing of it. This would create an ever worsening problem of dual ownership of this responsibility, split between the module-level FAM proxy and this SCC-level FAM proxy. Instead, this patch changes the SCC-level FAM proxy to work in terms of the module-level proxy and defer to it to handle much of the updates. It only does SCC-specific invalidation. This will become more important in subsequent patches that support more complex invalidaiton scenarios. Reviewers: jlebar Subscribers: mehdi_amini, mcrosier, mzolotukhin, llvm-commits Differential Revision: https://reviews.llvm.org/D27197 llvm-svn: 289317
2016-12-10 07:34:44 +01:00
template <>
bool FunctionAnalysisManagerModuleProxy::Result::invalidate(
Module &M, const PreservedAnalyses &PA,
ModuleAnalysisManager::Invalidator &Inv) {
[PM] Introduce the facilities for registering cross-IR-unit dependencies that require deferred invalidation. This handles the other real-world invalidation scenario that we have cases of: a function analysis which caches references to a module analysis. We currently do this in the AA aggregation layer and might well do this in other places as well. Since this is relative rare, the technique is somewhat more cumbersome. Analyses need to register themselves when accessing the outer analysis manager's proxy. This proxy is already necessarily present to allow access to the outer IR unit's analyses. By registering here we can track and trigger invalidation when that outer analysis goes away. To make this work we need to enhance the PreservedAnalyses infrastructure to support a (slightly) more explicit model for "sets" of analyses, and allow abandoning a single specific analyses even when a set covering that analysis is preserved. That allows us to describe the scenario of preserving all Function analyses *except* for the one where deferred invalidation has triggered. We also need to teach the invalidator API to support direct ID calls instead of always going through a template to dispatch so that we can just record the ID mapping. I've introduced testing of all of this both for simple module<->function cases as well as for more complex cases involving a CGSCC layer. Much like the previous patch I've not tried to fully update the loop pass management layer because that layer is due to be heavily reworked to use similar techniques to the CGSCC to handle updates. As that happens, we'll have a better testing basis for adding support like this. Many thanks to both Justin and Sean for the extensive reviews on this to help bring the API design and documentation into a better state. Differential Revision: https://reviews.llvm.org/D27198 llvm-svn: 290594
2016-12-27 09:40:39 +01:00
// If literally everything is preserved, we're done.
if (PA.areAllPreserved())
return false; // This is still a valid proxy.
[PM] Support invalidation of inner analysis managers from a pass over the outer IR unit. Summary: This never really got implemented, and was very hard to test before a lot of the refactoring changes to make things more robust. But now we can test it thoroughly and cleanly, especially at the CGSCC level. The core idea is that when an inner analysis manager proxy receives the invalidation event for the outer IR unit, it needs to walk the inner IR units and propagate it to the inner analysis manager for each of those units. For example, each function in the SCC needs to get an invalidation event when the SCC gets one. The function / module interaction is somewhat boring here. This really becomes interesting in the face of analysis-backed IR units. This patch effectively handles all of the CGSCC layer's needs -- both invalidating SCC analysis and invalidating function analysis when an SCC gets invalidated. However, this second aspect doesn't really handle the LoopAnalysisManager well at this point. That one will need some change of design in order to fully integrate, because unlike the call graph, the entire function behind a LoopAnalysis's results can vanish out from under us, and we won't even have a cached API to access. I'd like to try to separate solving the loop problems into a subsequent patch though in order to keep this more focused so I've adapted them to the API and updated the tests that immediately fail, but I've not added the level of testing and validation at that layer that I have at the CGSCC layer. An important aspect of this change is that the proxy for the FunctionAnalysisManager at the SCC pass layer doesn't work like the other proxies for an inner IR unit as it doesn't directly manage the FunctionAnalysisManager and invalidation or clearing of it. This would create an ever worsening problem of dual ownership of this responsibility, split between the module-level FAM proxy and this SCC-level FAM proxy. Instead, this patch changes the SCC-level FAM proxy to work in terms of the module-level proxy and defer to it to handle much of the updates. It only does SCC-specific invalidation. This will become more important in subsequent patches that support more complex invalidaiton scenarios. Reviewers: jlebar Subscribers: mehdi_amini, mcrosier, mzolotukhin, llvm-commits Differential Revision: https://reviews.llvm.org/D27197 llvm-svn: 289317
2016-12-10 07:34:44 +01:00
// If this proxy isn't marked as preserved, then even if the result remains
// valid, the key itself may no longer be valid, so we clear everything.
//
// Note that in order to preserve this proxy, a module pass must ensure that
// the FAM has been completely updated to handle the deletion of functions.
// Specifically, any FAM-cached results for those functions need to have been
// forcibly cleared. When preserved, this proxy will only invalidate results
// cached on functions *still in the module* at the end of the module pass.
[PM] Introduce the facilities for registering cross-IR-unit dependencies that require deferred invalidation. This handles the other real-world invalidation scenario that we have cases of: a function analysis which caches references to a module analysis. We currently do this in the AA aggregation layer and might well do this in other places as well. Since this is relative rare, the technique is somewhat more cumbersome. Analyses need to register themselves when accessing the outer analysis manager's proxy. This proxy is already necessarily present to allow access to the outer IR unit's analyses. By registering here we can track and trigger invalidation when that outer analysis goes away. To make this work we need to enhance the PreservedAnalyses infrastructure to support a (slightly) more explicit model for "sets" of analyses, and allow abandoning a single specific analyses even when a set covering that analysis is preserved. That allows us to describe the scenario of preserving all Function analyses *except* for the one where deferred invalidation has triggered. We also need to teach the invalidator API to support direct ID calls instead of always going through a template to dispatch so that we can just record the ID mapping. I've introduced testing of all of this both for simple module<->function cases as well as for more complex cases involving a CGSCC layer. Much like the previous patch I've not tried to fully update the loop pass management layer because that layer is due to be heavily reworked to use similar techniques to the CGSCC to handle updates. As that happens, we'll have a better testing basis for adding support like this. Many thanks to both Justin and Sean for the extensive reviews on this to help bring the API design and documentation into a better state. Differential Revision: https://reviews.llvm.org/D27198 llvm-svn: 290594
2016-12-27 09:40:39 +01:00
auto PAC = PA.getChecker<FunctionAnalysisManagerModuleProxy>();
if (!PAC.preserved() && !PAC.preservedSet<AllAnalysesOn<Module>>()) {
[PM] Support invalidation of inner analysis managers from a pass over the outer IR unit. Summary: This never really got implemented, and was very hard to test before a lot of the refactoring changes to make things more robust. But now we can test it thoroughly and cleanly, especially at the CGSCC level. The core idea is that when an inner analysis manager proxy receives the invalidation event for the outer IR unit, it needs to walk the inner IR units and propagate it to the inner analysis manager for each of those units. For example, each function in the SCC needs to get an invalidation event when the SCC gets one. The function / module interaction is somewhat boring here. This really becomes interesting in the face of analysis-backed IR units. This patch effectively handles all of the CGSCC layer's needs -- both invalidating SCC analysis and invalidating function analysis when an SCC gets invalidated. However, this second aspect doesn't really handle the LoopAnalysisManager well at this point. That one will need some change of design in order to fully integrate, because unlike the call graph, the entire function behind a LoopAnalysis's results can vanish out from under us, and we won't even have a cached API to access. I'd like to try to separate solving the loop problems into a subsequent patch though in order to keep this more focused so I've adapted them to the API and updated the tests that immediately fail, but I've not added the level of testing and validation at that layer that I have at the CGSCC layer. An important aspect of this change is that the proxy for the FunctionAnalysisManager at the SCC pass layer doesn't work like the other proxies for an inner IR unit as it doesn't directly manage the FunctionAnalysisManager and invalidation or clearing of it. This would create an ever worsening problem of dual ownership of this responsibility, split between the module-level FAM proxy and this SCC-level FAM proxy. Instead, this patch changes the SCC-level FAM proxy to work in terms of the module-level proxy and defer to it to handle much of the updates. It only does SCC-specific invalidation. This will become more important in subsequent patches that support more complex invalidaiton scenarios. Reviewers: jlebar Subscribers: mehdi_amini, mcrosier, mzolotukhin, llvm-commits Differential Revision: https://reviews.llvm.org/D27197 llvm-svn: 289317
2016-12-10 07:34:44 +01:00
InnerAM->clear();
return true;
}
[PM] Introduce the facilities for registering cross-IR-unit dependencies that require deferred invalidation. This handles the other real-world invalidation scenario that we have cases of: a function analysis which caches references to a module analysis. We currently do this in the AA aggregation layer and might well do this in other places as well. Since this is relative rare, the technique is somewhat more cumbersome. Analyses need to register themselves when accessing the outer analysis manager's proxy. This proxy is already necessarily present to allow access to the outer IR unit's analyses. By registering here we can track and trigger invalidation when that outer analysis goes away. To make this work we need to enhance the PreservedAnalyses infrastructure to support a (slightly) more explicit model for "sets" of analyses, and allow abandoning a single specific analyses even when a set covering that analysis is preserved. That allows us to describe the scenario of preserving all Function analyses *except* for the one where deferred invalidation has triggered. We also need to teach the invalidator API to support direct ID calls instead of always going through a template to dispatch so that we can just record the ID mapping. I've introduced testing of all of this both for simple module<->function cases as well as for more complex cases involving a CGSCC layer. Much like the previous patch I've not tried to fully update the loop pass management layer because that layer is due to be heavily reworked to use similar techniques to the CGSCC to handle updates. As that happens, we'll have a better testing basis for adding support like this. Many thanks to both Justin and Sean for the extensive reviews on this to help bring the API design and documentation into a better state. Differential Revision: https://reviews.llvm.org/D27198 llvm-svn: 290594
2016-12-27 09:40:39 +01:00
// Directly check if the relevant set is preserved.
bool AreFunctionAnalysesPreserved =
PA.allAnalysesInSetPreserved<AllAnalysesOn<Function>>();
// Now walk all the functions to see if any inner analysis invalidation is
// necessary.
for (Function &F : M) {
Optional<PreservedAnalyses> FunctionPA;
// Check to see whether the preserved set needs to be pruned based on
// module-level analysis invalidation that triggers deferred invalidation
// registered with the outer analysis manager proxy for this function.
if (auto *OuterProxy =
InnerAM->getCachedResult<ModuleAnalysisManagerFunctionProxy>(F))
for (const auto &OuterInvalidationPair :
OuterProxy->getOuterInvalidations()) {
AnalysisKey *OuterAnalysisID = OuterInvalidationPair.first;
const auto &InnerAnalysisIDs = OuterInvalidationPair.second;
if (Inv.invalidate(OuterAnalysisID, M, PA)) {
if (!FunctionPA)
FunctionPA = PA;
for (AnalysisKey *InnerAnalysisID : InnerAnalysisIDs)
FunctionPA->abandon(InnerAnalysisID);
}
}
// Check if we needed a custom PA set, and if so we'll need to run the
// inner invalidation.
if (FunctionPA) {
InnerAM->invalidate(F, *FunctionPA);
continue;
}
// Otherwise we only need to do invalidation if the original PA set didn't
// preserve all function analyses.
if (!AreFunctionAnalysesPreserved)
InnerAM->invalidate(F, PA);
}
[PM] Support invalidation of inner analysis managers from a pass over the outer IR unit. Summary: This never really got implemented, and was very hard to test before a lot of the refactoring changes to make things more robust. But now we can test it thoroughly and cleanly, especially at the CGSCC level. The core idea is that when an inner analysis manager proxy receives the invalidation event for the outer IR unit, it needs to walk the inner IR units and propagate it to the inner analysis manager for each of those units. For example, each function in the SCC needs to get an invalidation event when the SCC gets one. The function / module interaction is somewhat boring here. This really becomes interesting in the face of analysis-backed IR units. This patch effectively handles all of the CGSCC layer's needs -- both invalidating SCC analysis and invalidating function analysis when an SCC gets invalidated. However, this second aspect doesn't really handle the LoopAnalysisManager well at this point. That one will need some change of design in order to fully integrate, because unlike the call graph, the entire function behind a LoopAnalysis's results can vanish out from under us, and we won't even have a cached API to access. I'd like to try to separate solving the loop problems into a subsequent patch though in order to keep this more focused so I've adapted them to the API and updated the tests that immediately fail, but I've not added the level of testing and validation at that layer that I have at the CGSCC layer. An important aspect of this change is that the proxy for the FunctionAnalysisManager at the SCC pass layer doesn't work like the other proxies for an inner IR unit as it doesn't directly manage the FunctionAnalysisManager and invalidation or clearing of it. This would create an ever worsening problem of dual ownership of this responsibility, split between the module-level FAM proxy and this SCC-level FAM proxy. Instead, this patch changes the SCC-level FAM proxy to work in terms of the module-level proxy and defer to it to handle much of the updates. It only does SCC-specific invalidation. This will become more important in subsequent patches that support more complex invalidaiton scenarios. Reviewers: jlebar Subscribers: mehdi_amini, mcrosier, mzolotukhin, llvm-commits Differential Revision: https://reviews.llvm.org/D27197 llvm-svn: 289317
2016-12-10 07:34:44 +01:00
// Return false to indicate that this result is still a valid proxy.
return false;
}
}
[PM] Change the static object whose address is used to uniquely identify analyses to have a common type which is enforced rather than using a char object and a `void *` type when used as an identifier. This has a number of advantages. First, it at least helps some of the confusion raised in Justin Lebar's code review of why `void *` was being used everywhere by having a stronger type that connects to documentation about this. However, perhaps more importantly, it addresses a serious issue where the alignment of these pointer-like identifiers was unknown. This made it hard to use them in pointer-like data structures. We were already dodging this in dangerous ways to create the "all analyses" entry. In a subsequent patch I attempted to use these with TinyPtrVector and things fell apart in a very bad way. And it isn't just a compile time or type system issue. Worse than that, the actual alignment of these pointer-like opaque identifiers wasn't guaranteed to be a useful alignment as they were just characters. This change introduces a type to use as the "key" object whose address forms the opaque identifier. This both forces the objects to have proper alignment, and provides type checking that we get it right everywhere. It also makes the types somewhat less mysterious than `void *`. We could go one step further and introduce a truly opaque pointer-like type to return from the `ID()` static function rather than returning `AnalysisKey *`, but that didn't seem to be a clear win so this is just the initial change to get to a reliably typed and aligned object serving is a key for all the analyses. Thanks to Richard Smith and Justin Lebar for helping pick plausible names and avoid making this refactoring many times. =] And thanks to Sean for the super fast review! While here, I've tried to move away from the "PassID" nomenclature entirely as it wasn't really helping and is overloaded with old pass manager constructs. Now we have IDs for analyses, and key objects whose address can be used as IDs. Where possible and clear I've shortened this to just "ID". In a few places I kept "AnalysisID" to make it clear what was being identified. Differential Revision: https://reviews.llvm.org/D27031 llvm-svn: 287783
2016-11-23 18:53:26 +01:00
AnalysisSetKey CFGAnalyses::SetKey;
[PM] Introduce the facilities for registering cross-IR-unit dependencies that require deferred invalidation. This handles the other real-world invalidation scenario that we have cases of: a function analysis which caches references to a module analysis. We currently do this in the AA aggregation layer and might well do this in other places as well. Since this is relative rare, the technique is somewhat more cumbersome. Analyses need to register themselves when accessing the outer analysis manager's proxy. This proxy is already necessarily present to allow access to the outer IR unit's analyses. By registering here we can track and trigger invalidation when that outer analysis goes away. To make this work we need to enhance the PreservedAnalyses infrastructure to support a (slightly) more explicit model for "sets" of analyses, and allow abandoning a single specific analyses even when a set covering that analysis is preserved. That allows us to describe the scenario of preserving all Function analyses *except* for the one where deferred invalidation has triggered. We also need to teach the invalidator API to support direct ID calls instead of always going through a template to dispatch so that we can just record the ID mapping. I've introduced testing of all of this both for simple module<->function cases as well as for more complex cases involving a CGSCC layer. Much like the previous patch I've not tried to fully update the loop pass management layer because that layer is due to be heavily reworked to use similar techniques to the CGSCC to handle updates. As that happens, we'll have a better testing basis for adding support like this. Many thanks to both Justin and Sean for the extensive reviews on this to help bring the API design and documentation into a better state. Differential Revision: https://reviews.llvm.org/D27198 llvm-svn: 290594
2016-12-27 09:40:39 +01:00
AnalysisSetKey PreservedAnalyses::AllAnalysesKey;